Category Archives: Students

Items for students and others, interested in learning about science and engineering and the application of science in our lives. We post many of the general interest items here.

Mihaly Csikszentmihalyi: Creativity, Fulfillment and Flow

“After a certain basic point, which translates, more or less, to just a few thousand dollars above the minimum poverty level, increases in material well being don’t see to affect how happy people are.”

The speech includes, the first purpose of incorporation at Sony:

To establish a place of work where engineers can feel the joy of technological innovation, be aware of their mission to society, and work to their heart’s content.

Excellent books by Mihaly Csikszentmihalyi:
Flow: The Psychology of Optimal Experience by Mihaly Csikszentmihalyi, 1991. People enter a flow state when they are fully absorbed in activity during which they lose their sense of time and have feelings of great satisfaction.
Good Business: Leadership, Flow, and the Making of Meaning.
Creativity: Flow and the Psychology of Discovery and Invention by Mihaly Csikszentmihalyi, 1997. Drawing on hundreds of interviews with exceptional people, from biologists and physicists to politicians and business leaders to poets and artists, the author uses his famous “flow” theory to explain the creative process.

What Dogs Reveal About Evolution

From, The Greatest Show on Earth: The Evidence for Evolution by Richard Dawkins

All breeds of dogs are domesticated wolves: not jackals, not coyotes and not foxes.
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Coppinger points out that when domestic animals break free and go feral for many generations, they usually revert to something close to their wild ancestor. We might expect feral dogs, therefore, to become rather wolf-like. But this doesn’t happen. Instead, dogs left to go feral seem to become the ubiquitous “village dogs” – “pye-dogs” – that hang around human settlements all over the Third World. This encourages Coppinger’s belief that the dogs on which human breeders finally went to work were wolves no longer. They had already changed themselves into dogs: village dogs, pye-dogs, perhaps dingos.

Real wolves are pack hunters. Village dogs are scavengers that frequent middens and rubbish dumps.
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Belyaev and his colleagues (and successors, for the experimental programme continued after his death) subjected fox cubs to standardised tests in which an experimenter would offer a cub food by hand, while trying to stroke or fondle it. The cubs were classified into three classes. Class III cubs were those that fled from or bit the person. Class II cubs would allow themselves to be handled, but showed no positive responsiveness to the experimenters. Class I cubs, the tamest of all, positively approached the handlers, wagging their tails and whining. When the cubs grew up, the experimenters systematically bred only from this tamest class.

After a mere six generations of this selective breeding for tameness, the foxes had changed so much that the experimenters felt obliged to name a new category, the “domesticated elite” class, which were “eager to establish human contact, whimpering to attract attention and sniffing and licking experimenters like dogs.” At the beginning of the experiment, none of the foxes were in the elite class. After ten generations of breeding for tameness, 18 per cent were “elite”; after 20 generations, 35 per cent; and after 30 to 35 generations, “domesticated elite” individuals constituted between 70 and 80 per cent of the experimental population.
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The tame foxes not only behaved like domestic dogs, they looked like them. They lost their foxy pelage and became piebald black and white, like Welsh collies. Their foxy prick ears were replaced by doggy floppy ears. Their tails turned up at the end like a dog’s, rather than down like a fox’s brush. The females came on heat every six months like a bitch, instead of every year like a vixen. According to Belyaev, they even sounded like dogs.

These dog-like features were side- effects. Belyaev and his team did not deliberately breed for them, only for tameness.

The famous domesticated silver fox experiment offers interesting insight into animal traits and evolution.

Capuchin Monkeys Using Stone Tools

This BBC documentary “Clever Monkeys”, narrated by David Attenborough, shows Capuchin monkeys in Brazil using heavy stones to break open aged palm nuts.

Microbes Flourish In Healthy People

Bugs Inside: What Happens When the Microbes That Keep Us Healthy Disappear? by Katherine Harmon

The human body has some 10 trillion human cells—but 10 times that number of microbial cells. So what happens when such an important part of our bodies goes missing?
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“Someone who didn’t have their microbes, they’d be naked,” says Martin Blaser, a professor of microbiology and chair of the Department of Medicine at New York University Langone Medical Center in New York City.
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Even though it is such an apparently integral and ancient aspect of human health, scientists are still grasping for better ways to study human microbiota—before it changes beyond historical recognition. Borrowing models from outside of medicine has helped many in the field gain a better understanding of this living world within us. “The important concept is about extinctions,” Blaser says. “It’s ecology.”
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The first step in understanding these systems is simply taking stock of what archaea, bacteria, fungi, protozoa and viruses are present in healthy individuals. This massive micro undertaking has been ongoing since 2007 through the National Institutes of Health’s (NIH) Human Microbiome Project. So far it has turned up some surprisingly rich data, including genetic sequencing for some 205 of the different genera that live on healthy human skin.

Despite the flood of new data, Foxman laughs when asked if there is any hope for a final report from the Human Microbiome Project any time soon. “This is the very, very beginning,” she says, comparing this project with the NIH’s Human Genome Project, which jump-started a barrage of new genetic research. “There are basic, basic questions that we don’t know the answers to,” she says, such as how different microbiota are between random individuals or family members; how much microbiota change over time; or how related the microbiota are to each other on or inside a person’s body.

Fungus-gardening Ant Species Has Given Up Sex Completely

The complete asexuality of a widespread fungus-gardening ant, the only ant species in the world known to have dispensed with males entirely, has been confirmed by a team of Texas and Brazilian researchers.

photo of christian rabeling excavating ants in Brazil

Graduate student Christian Rabeling excavating fungus-farming ant nests in Brasilia.

Most social insects—the wasps, ants and bees—are relatively used to daily life without males. Their colonies are well run by swarms of sterile sisters lorded over by an egg-laying queen. But, eventually, all social insect species have the ability to produce a crop of males who go forth in the world to fertilize new queens and propagate.

Queens of the ant Mycocepurus smithii reproduce without fertilization and males appear to be completely absent, report Christian Rabeling, Ulrich Mueller and their Brazilian colleagues in open access journal PLoS ONE this week.

“Animals that are completely asexual are relatively rare, which makes this is a very interesting ant,” says Rabeling, an ecology, evolution and behavior graduate student at The University of Texas at Austin. “Asexual species don’t mix their genes through recombination, so you expect harmful mutations to accumulate over time and for the species to go extinct more quickly than others. They don’t generally persist for very long over evolutionary time.”

Previous studies of the ants from Puerto Rico and Panama have pointed toward the ants being completely asexual. One study in particular, by Mueller and former graduate student Anna Himler (now at Arizona State University), showed that the ants reproduced in the lab without males, and that no amount of stress induced the production of males.

Scientists believed that specimens of male ants previously collected in Brazil in the 1960s could be males of M. smithii. If males of the species existed, it would suggest that—at least from time to time—the ants reproduce sexually.

Rabeling analyzed the males in question and discovered that they belonged to another closely related (sexually reproducing) species of fungus-farmer, Mycocepurus obsoletus, thus establishing that no males are known to exist for M. smithii. He also dissected reproducing M. smithii queens from Brazil and found that their sperm storage organs were empty.

Taken together with the previous studies of the ants, Rabeling and his colleagues have concluded that the species is very likely to be totally asexual across its entire range, from Northern Mexico through Central America to Brazil, including some Caribbean islands.

As for the age of the species, the scientists estimate the ants could have first evolved within the last one to two million years, a very young species given that the fungus-farming ants evolved 50 million years ago.

Rabeling says he is using genetic markers to study the evolution and systematics of the fungus-gardening ants and this will help determine the date of the appearance and genetic mechanism of asexual reproduction more precisely in the near future.

Full press release

Arduino: Open Source Programmable Hardware

Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It’s intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.

Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The microcontroller on the board is programmed using the Arduino programming language and the Arduino development environment.

The boards can be built by hand or purchased preassembled; the software can be downloaded for free. The hardware reference designs (CAD files) are available under an open-source license, you are free to adapt them to your needs.

See the getting started guide to try for yourself.

Printing Bone, Muscle and More

A Pittsburgh-based research team has created and used an innovative ink-jet system to print “bio-ink” patterns that direct muscle-derived stem cells from adult mice to differentiate into both muscle cells and bone cells.

The custom-built ink-jet printer, developed at Carnegie Mellon’s Robotics Institute, can deposit and immobilize growth factors in virtually any design, pattern or concentration, laying down patterns on native extracellular matrix-coated slides (such as fibrin). These slides are then placed in culture dishes and topped with muscle-derived stem cells (MDSCs). Based on pattern, dose or factor printed by the ink-jet, the MDSCs can be directed to differentiate down various cell-fate differentiation pathways (e.g. bone- or muscle-like).

“This system provides an unprecedented means to engineer replacement tissues derived from muscle stem cells,” said Johnny Huard, professor of orthopedic surgery at the University of Pittsburgh School of Medicine and director of the Stem Cell Research Center at Children’s Hospital of UPMC. Huard has long-standing research findings that show how muscle-derived stem cells (MDSCs) from mice can repair muscle in a model for Duchenne Muscular Dystrophy, improve cardiac function following heart failure, and heal large bone and articular cartilage defects.

Weiss and Campbell, along with graduate student Eric Miller, previously demonstrated the use of ink-jet printing to pattern growth factor “bio-inks” to control cell fates. For their current research, they teamed with Phillippi, Huard and biologists of the Stem Cell Research Center at Children’s Hospital to gain experience in using growth factors to control differentiation in populations of MDSCs from mice.

The team envisions the ink-jet technology as potentially useful for engineering stem cell-based therapies for repairing defects where multiple tissues are involved, such as joints where bone, tendon, cartilage and muscle interface. Patients afflicted with conditions like osteoarthritis might benefit from these therapies, which incorporate the needs of multiple tissues and may improve post-treatment clinical outcomes.

The long-term promise of this new technology could be the tailoring of tissue-engineered regenerative therapies. In preparation for preclinical studies, the Pittsburgh researchers are combining the versatile ink-jet system with advanced real-time live cell image analysis developed at the Robotics Institute and Molecular Biosensor and Imaging Center to further understand how stem cells differentiate into bone, muscle and other cell types.

Albatross Chicks Fed Plastic Ocean Pollution by Parents

photo of dead Albatross chick

See more photographs of remains of albatross chicks on the Midway Atoll, a tiny stretch of sand and coral near the middle of the North Pacific.

The nesting babies are fed bellies-full of plastic by their parents, who soar out over the vast polluted ocean collecting what looks to them like food to bring back to their young. On this diet of human trash, every year tens of thousands of albatross chicks die on Midway from starvation, toxicity, and choking.

To document this phenomenon as faithfully as possible, none of the plastic in any of these photographs was moved, placed, manipulated, arranged, or altered in any way. These images depict the untouched stomach contents of baby birds in one of the world’s most remote marine sanctuaries, more than 2000 miles from the nearest continent.

Prion Proteins, Without Genes, Can Evolve

‘Lifeless’ prion proteins are ‘capable of evolution’

scientists transferred prion populations from brain cells to other cells in culture and observed the prions that adapted to the new cellular environment out-competed their brain-adapted counterparts. When returned to the brain cells, the brain-adapted prions again took over the population.

Charles Weissmann, head of Scripps Florida’s department of infectology who led the study, said: “On the face of it, you have exactly the same process of mutation and adaptive change in prions as you see in viruses.

“This means that this pattern of Darwinian evolution appears to be universally active. “In viruses, mutation is linked to changes in nucleic acid sequence that leads to resistance.

“Now, this adaptability has moved one level down- to prions and protein folding – and it’s clear that you do not need nucleic acid (DNA or RNA) for the process of evolution.”
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He said: “The prion protein is not a clone, it is a quasi-species that can create different protein strains even in the same animal. “The abnormal prion proteins multiply by converting normal prion proteins.

“The implication of Charles Weissmann’s work is that it would be better to cut off that supply of normal prion proteins rather than risk the abnormal prion adapting to a drug and evolving into a new more virulent form.

Engineering a Better Football

The football (soccer ball) for the 2010 FIFA World Cup features completely new, ground-breaking technology. Eight 3-D spherically formed panels are moulded together, harmoniously enveloping the inner carcass. The result is an energetic unit combined with perfect roundness.

Aero grooves create the clearly visible profile on the ball’s surface. The Grip’n’Groove profile circles around the entire ball in an optimal aerodynamic way. The integrated grooves provide unmatched flight characteristics, making this the most stable and most accurate Adidas football. The ground breaking performance features have been confirmed in comprehensive comparison tests at Loughborough University in England and countless checks in wind tunnel and the Adidas football laboratory in Scheinfeld, Germany.

The process, shown in the video, for manufacturing the footballs is way more complicate than I thought it would be.